Lactation Data

By GrowingDeer,

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Earlier you answered my question on collecting harvest data for our co-op, thank you.  I find it interesting that the professional biologist that we work with pushes quite heavily for a sample of fetuses for data.  You only require your hunters to give a yes or no on whether or not the doe is lactating until mid December.  Could lactation data be used as a substitute for collecting fetuses? The main reason we are collecting fetuses is to determine when the doe was bred.  Am I missing something on what can be learned by recording the lactating data?



The biologist you work with may need conception date data based on fetuses for a specific reason.  I certainly believe that the more data collected the better!  However, I’ve found that many clubs don’t do a stellar job of collecting harvest data.  Not measuring a fetus correctly may cause a significant difference in estimating the conception date.  Such errors are common when multiple club members collect data.  If your club is collecting the data, it would be appropriate to ask the biologist how the data is being used.

Lactation data is not a substitute for fetal data.  Lactation data simply indicates that a doe has at least one nursing fawn.  It doesn’t give any indication how many fawns were nursing.  It doesn’t indicate if the fawn (or fawns) is still alive.  The percentage of yearling does that are lactating during the appropriate time of year is a good measure of the herd’s health.  If a significant number of yearling does produced fawns, the herd is not experiencing nutritional stress.  I’ve worked with herds in northern New York that were very unhealthy.  They still produced gads of twin fetuses, but usually produced less than 25 fawns per 100 adult does.  Fetal data from that herd would have been very misleading.  Lactation data and observation data matched closely and indicated that the does simply were under too much nutritional stress to carry fawns to full term or keep them alive until fall.

Growing Deer together,